The Security variant was first manufactured in the Misriah Armory facility on Mars in 2528. After Mark V was released, this armor was adapted to its use. Like most MJOLNIR variants, the later model of the Security helmet had been upgraded to be compatible with all MJOLNIR Mark VI variants.[1]

The GEN2 variant's helmet has two watchdog AIs hovering at the edges of the SECURITY VISR interface, alert for cyberintrusion attempts and sensor anomalies that could indicate subversion of connected surveillance networks. The armor also seamlessly integrates with Navy networks and security constructs.[5]

SECURITY [GEN1] helmets continued to be used by Misriah Armory's executive protection teams after the Covenant War. These helmets have been upgraded to be compatible with GEN2 systems, though corporate representatives balk at releasing its custom VISR.[6]

Helmet Description: The Mjolnir(m) variant was manufactured at the Misrah Armories Facility on Mars in 2528. It has been upgraded and modified to be compatible with all current-issue armor variants.

The helmet's most noticeable feature is the larger, more prominent "figure-eight" shaped visor which looks almost bug-eyed. It bears resemblance to that of a modern day fighter jet pilot helmet. This helmet is inspired by the protagonist of Marathon, although the mouth is covered. The helmet is large with a small raised section on the forehead in the form of the Marathon logo. Wearing the helmet will also add a small antenna and dial to the right shoulder.

The prominent bug-eyed shape has been toned up, and the helmet looks bigger overall.

Unlock: Officially, the Security shoulders unlock when the player has attained at least 750 Gamerscore points from Halo 3. However, the shoulders are renowned and well-known bugged items.

Shoulders description: The Mjolnir Mark V(m) Powered Assault Armor was originally manufactured in 2528 and recently upgraded to be compatible with all current-issue armor variants.

The shoulder pieces are quite largely rounded, with a section with an upper center, trapezium-shaped arm guard going out the bottom and a rounded section above that. It should be noted that this shoulder permutation is prone to a glitch that may cause you to not unlock them until you have 1000 gamerscore; however, another glitch has occurred that unlocks the Security shoulders before reaching 750 gamerscore points in Halo 3.

The Security armor does not have a chest plate, although wearing the helmet will give the player a distinct "antenna and dial" on the right side of the back plate. This may be a reference to the antenna Master Chief had in the pre-Halo: Combat Evolved at the Mac World Trailer.

Helmet Description: Two watchdog AIs hover at the edges of the SECURITY VISR interface, alert for cyberintrusion attempts and sensor anomalies that could indicate subversion of connected surveillance networks.

Armor Description: Built to Spartan branch requirements for ship and station defense personnel, SECURITY armor seamlessly integrates with Navy networks and security constructs.[7]

Helmet description: SECURITY [GEN1] helmets continued to be used by Misriah Armory's executive protection teams after the Covenant War. These helmets have been upgraded to be compatible with GEN2 systems, though corporate representatives balk at releasing its custom VISR.

The SECURITY-class helmet (as well as the Mark VI version's pauldrons) is based on that worn by the protagonist of the Marathon series, who is known only as the "Security Officer". The Marathon logo is featured prominently on the Mark VI version of the helmet (just above the visor) in Halo 3. The Mark V Security helmet in Halo: Reach and Halo 5: Guardians lacks the symbol, likely due to intellectual property concerns (as Bungie retained the Marathon IP after leaving Microsoft). However, the Reclaimer symbol (a modified version of the Marathon logo) appears on the GEN2 version of the helmet in Halo 5: Guardians.